Biotechnology and its Applications


Important Questions

Question 1. Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because –

(a) bacteria are resistant to the toxin

(b) toxin is immature;

(c) toxin is inactive;

(d) bacteria enclose toxin in a special sac.


(c) toxin is inactive:

In bacteria, the toxin is present in an inactive form, called prototoxin, which gets converted into active form when it enters the body of an insect.


Question 2. What are transgenic bacteria? Illustrate using any one example.

Ans: Transgenic bacteria contain foreign gene that is intentionally introduced into its genome. They are manipulated to express the desirable gene for the production of various commercially important products.

An example of transgenic bacteria is E.coli. In the plasmid of E.coli, the two DNA sequences corresponding to A and B chain of human insulin are i